20th anniversary: Quote for Smash.
30th anniversary: Cave Story is remade again for brainjack mind upload.
40th anniversary: The world is divided between 3 races, genetically enhanced superhumans, electronic consciousnesses, and the underbeings who have not evolved. They all agree on a delicate peace based on mutual agreement that Cave Story is the greatest game of all time. This wasn't an easy peace to achieve. Many Fortnite players had to accept conversion to the true path of Cave Story or be fed to the datawurm.
50th anniversary: Though Pixel's flesh has perished in the nuclear fires of the Armageddon wars, his mind has merged with the datastream allowing him to more easily create games and gift them unto the masses by sheer thought alone. Kero Blaster has seen its 5th spinoff where you play through the drudgery of Nanao's past as an office worker. It is declared game of the decade.
60th anniversary: Man and machine are one race now and have extended their reach to the stars. Pixel has migrated his consciousness to the core of the galaxy to contemplate his next work in the vast solitude of infinity.
70th anniversary: A cave story prequel is teased in the ending of Half Life 3.
80th anniversary: Cave Story prequel is scrapped and instead Guxt 2 is released, only it's played by piloting an actual space ship and fighting actual alien invaders.
90th anniversary: All is quiet. Some question if Pixel has abandoned them. The moon is de-orbited during a conflict that arose when someone was heard to say "Cave Story? Isn't that just a ripoff of Undertale?"
100th anniversary: The year is 3004. Cave Story 2 is completed, but Pixel looks on at the unworthy masses and shakes his head. "They are not ready," he says to himself.